Funds Held for Clients and Corporate Investments (Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity) (Details) - USD ($) $ in Millions |
Feb. 28, 2018 |
May 31, 2017 |
|---|---|---|
| Funds Held for Clients and Corporate Investments [Abstract] | ||
| Due in one year or less, Amortized cost | $ 317.9 | |
| Due after one year through three years, Amortized cost | 820.5 | |
| Due after three years through five years, Amortized cost | 998.1 | |
| Due after five years, Amortized cost | 1,654.0 | |
| Available-for-sale securities, Amortized cost | 3,790.5 | $ 4,581.2 |
| Due in one year or less, Fair value | 317.9 | |
| Due after one year through three years, Fair value | 819.9 | |
| Due after three years through five years, Fair value | 990.7 | |
| Due after five years, Fair value | 1,627.1 | |
| Available-for-sale securities, Fair value | $ 3,755.6 | $ 4,613.2 |
| X | ||||||||||
- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing after the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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| X | ||||||||||
- Definition Fair value of available-for-sale debt securities maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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| X | ||||||||||
- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing after the first fiscal year through the third fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition Fair value of available-for-sale debt securities maturing after the first fiscal year through the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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| X | ||||||||||
- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing after the third fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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| X | ||||||||||
- Definition Fair value of available-for-sale debt securities maturing after the third fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition Funds held for clients and corporate investments. No definition available.
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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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